I was re-reading the Jon spoiler chapter on Martin's website today, and this little bit struck me:

Once they had been six, five whimpering blindly in the snow beside their dead mother, and him alone, the pale one, crawling off into the trees on shaky legs as his litter mates sucked cool milk from hard dead nipples. Now only four remained of the six born that day, and one of those was lost and gone.

Which made me wonder who the "lost and gone" direwolf was. Ther four wolves in question are Nymeria, Summer, Shaggydog and Ghost (the "narrator"). At first I was thinking it was Shaggydog, since we haven't heard anything about Rickon since the end of Clash of Kings, but now I wonder if it night not be Summer. At the end of Storm of Swords, Jon makes passing reference to having no sense of his wolf after he passed south of the wall with the wildlings. Does the Wall not only protect the south, but also prevent some forms of magic from passing through, or whatever it is that the worgs and Stark children share? The only person who has been able to contact someone beyond the wall has been Bran, and we know he is special in some way.

It may not be much, or anything really, but I was wondering if anyone else had any thoughts.

I would assume it is Arya's Nymeria.

I also assumed it is Nymeria, because she is separated from her human ... counterpart?

• Lady was killed by Ned
• Grey Wind was killed by the Freys
• Nymeria was set lose by Arya, which is why Lady had to be killed in her place - so this is the "lost one."
• Summer should still be with Bran
• Shaggydog should still be with Rickon
• Ghost returned to Jon

So 4 left of the 6 with 1 missing.

Actually, after rereading the spoiler chapter myself, I think you're right, JerusalemJones. Ghost has a pretty clear idea where Shaggydog (killing a goat) and Nymeria (howling in a choire) are. So why should he refer to Nymeria as "lost and gone"? It also makes sense that the anti-magic Wall would prevent the telepathic link between the Stark-Kids and the wolfes. So Summer is the lost one, not for Bran, but for Ghost. Good catch!

Its Nymeria. She is the only one separated from her Stark kid.

Please read the chapter again. I thought the same thing until an hour ago.

No its definitely Summer who is "lost". If you reread the chapter, Ghost has a very clear idea of where Nymeria is, but cannot "see" Summer any longer. Either Summer is out of range, or there's something weird going on with the Wall/Far North.

Nice to see you around these parts Mr. Long.

As Sam said:

"The Wall. The Wall is more than just ice and stone, he said. There are spells woven into it ... old ones, and strong. He cannot pass beyond the Wall."

(It's nice to be able to search for "the wall is more" and find what I vaguely remember)

It makes Bran's early experiences with the three-eyed crow (when he looks to the far north and sees something terrible) all the more extraordinary.